Steering device for a drive-by-wire vehicle

ABSTRACT

A steering device ( 1 ) for drive-by-wire functions in a vehicle comprises a base ( 2 ) which can be fixed to the vehicle interior at the location of the driver, and two steering grips ( 3, 4 ) at opposite sides of the base, which steering grips each can be gripped by a hand of the driver, said steering grips being coupled and being moveable with respect to the base in mutually opposite directions.

[0001] The invention is related to a steering device for a drive-by-wirevehicle. Such vehicles have controls which are fully or partly operatedby means of electric cables. Examples are the electric control ofbrakes, of the clutch and the gearbox ect. so as to avoid the use ofhydraulic and/or mechanical control lines.

[0002] The steering function of a vehicle is usually fully mechanical,be it that electric or hydraulic power assisted steering is widely used.On the other hand, electrically operated steering devices have beenproposed which are controllable by means of a joystick. Such joystickdevices are more and more applied in e.g. aeroplanes. The application ofsuch joystick devices in road vehicles seems however less acceptable tothe average car driver. This is caused by the fact that the “feel” andcontrol properties of a joystick are quite different from theseassociated with a conventional steering wheel.

[0003] The object of the invention is therefore to provide a steeringdevice which is suitable for drive-by-wire applications, but which doesnot differ appreciably from the conventional steer wheel. This object isachieved by means of a steering device for drive-by-wire functions in avehicle, said steering device comprising a base which can be fixed tothe vehicle interior at the location of the driver, and two steeringgrips at opposite sides of the base, which steering grips each can begripped by a hand of the driver, said steering grips being coupled andbeing moveable with respect to the base in mutually opposite direction.The base can either be fixed permanently or through a click-on system inthe vehicle interior. Also, the base can be fixed to a moveable support,which can be changed between a left-hand drive or a right-hand driveposition.

[0004] The steering device according to the invention does not providethe usual rotational steering movement of the conventional steeringwheel, but instead provides opposite movements of a pair of handgrips.Thus, the driver of the car which is equipped with the steering deviceaccording to the invention can still grip the steering grips with bothhands. Also, the driver can steer by gripping only one steering gripwith one hand.

[0005] Moreover, as in the case of the conventional steering wheel,movements in opposite directions are imposed on the pair of steeringgrips, the movements of which to a large extend resemble the oppositerotational movements on the opposite sides of the convention steeringwheel.

[0006] As a result, the driver does not have to adjust his normaldriving habits too much, which would make the steering device accordingto the invention quite acceptable to the average driver.

[0007] In order to provide the driver with the normal “feel” of theconventional steering wheel, which “feel” provides useful informationconcerning car behaviour etc, the steering grips are moveable from theirneutral position under the influence of a resistance device simulatingsteering resistance, e.g. a spring or an electric motor. Furthermore, atleast one sensor is provided for sensing a movement of the handgrips,said sensor being in closed loop configuration with a steering controldevice.

[0008] The coupled movement of the steering grips may be obtained inseveral ways. For instance, the steering grips can be coupled by meansof a tiltable lever, which at each end engages a respective steeringgrip, and which midway between said ends is pivotably connected to thebase. The lever engages each steering grip through a slidable/pivotableconnection.

[0009] The steering grips may be carried out with any convenient shapewhich enhances the driver comfort. For instance, each steering grip mayhave a straight or arc-shaped outer circumference. Also, each steeringgrip can have an arc-shaped rod, connected to a slide which is slidablesupported on the base, the rod and slide of each steering grip beingconnected through a spoke.

[0010] Furthermore, the base carries a head-up screen or LCD screen fordisplaying vehicle control and performance data, telecommunication meanse.g. telephone, route planning and an airbag.

[0011] With the aim of enhancing the proper use of the steering deviceof the invention, signalling means are provided for signalling aleft-hand and a right-hand turn.

[0012] The steering grips may be movable in parallel, or at any anglewith respect to each other. Each steering grip can be slidable along thebase by means of a linear bearing e.g. a plain bearing. Said base may beused for other functions, and may comprise a display and operatingbuttons, e.g. for accelerating/decelerating, shifting indicators,lightning, route planning, telephone. According to a further embodiment,each steering grip can be slidable according to a curved trajectory, thecurbed trajectory of each steering grip being formed according to acircular arc.

[0013] A hand rest can also form part of the base. This hand restprovides a convenient support for the hands of the driver, and alsoprotects the handgrips from accidental actuation by means of thedriver's knee.

[0014] In that case, each steering grip can have a tooth rack which iscurved according to the circular arcs, pinions being rotatablyaccommodated in the base which engage the curved tooth racks.

[0015] The invention is also related to a combination comprising asteering device according to one of the preceding claims, and amechanically operated backup system for controlling prime vehicle safetyfunction, such as steering and braking in case of a power failure.According to a preferred embodiment, locking means are provided forlocking the steering grips with respect to the base in the case of apower failure, said fixed base being linked to the backup system andbeing released from a fixed position to a rotatable position in the caseof said power failure.

[0016] Also, the steering device may be applied in combination with asteering column structure comprising one or more foot pedals for e.g.acceleration and/or breaking.

[0017] The invention will now be described further with reference to anembodiment of the steering device according to the invention as shown inthe drawings.

[0018]FIG. 1 shows a view in perspective of the steering deviceaccording to the invention.

[0019]FIG. 2 shows a back view.

[0020] FIGS. 3-5 show views in perspective from the underside, with thesteering grips in different positions.

[0021]FIGS. 6, 7 and 8 show further embodiments.

[0022] The steering device 1 according to the invention comprises a base2 which can be fixed to the vehicle interior at the location of thedriver. This connection can be permanent, but can also be carried out asa click-on connection. In the latter case, the steering device can beapplied or taken away at will, and can also be applied at the left handor right hand driver's seat in case the required provisions areavailable in the dashboard of the vehicle.

[0023] Moreover, the steering device 1 may be carried out as aretractable unit. Upon driving, the steering device may in that case bein its normal steering position. When a car is parked, the steeringdevice can be retracted so as to enable a comfortable seating procedure.

[0024] The steering device 1 furthermore comprises left hand and righthand steering grips 3, 4 at opposite sides of the base. These steeringgrips 3, 4 can be gripped by the hands of a driver; also, the driver mayof course exert a steering action by gripping a single steering gripwith only one hand.

[0025] For carrying out the steering movements, the steering grips 3, 4are slid along the base 2 in mutually opposite direction, as shown inthe FIGS. 3-5.

[0026] To that end, the base 2 carries a pivot 7 by means of which thelever 5 can be pivoted into the different angular positions as shown inthe FIGS. 3-5.

[0027] At its opposite ends, the lever 5 is engaging the steering grips3. The connections 6 between the respective ends of the lever 5 and thesteering grips 3, 4 allow relative displacements in the longitudinaldirection of the lever 5.

[0028] In the embodiment shown, the steering grips 3, 4 each have anarch-shaped part, which by means of a spoke 15 is connected to the slidepart 14. This slide part 14 is, in a manner known per se, e.g. by alinear bearing 9, connected to the base 2.

[0029] The base 2 furthermore comprises operating buttons 11 forcarrying out several functions.

[0030] Moreover, signalling means 16 are provided which indicate thesteering direction as carried out by the driver.

[0031] A route information planner is also installed on the base 2.

[0032] Alternatively, also an airbag may be provided.

[0033] In the embodiment of FIG. 6, the steering device 1 is combinedwith a steering support column structure 18, onto which also pedals 19,e.g. for accelerating or braking, are connected as a unity.

[0034] The embodiment of FIG. 7 has handgrips 3, 4 which are connectedthrough a hinge 34. Moreover, a hand rest 25 is provided.

[0035] The further embodiment of FI. 8 comprises handgrips 3, 4 whichare slideable along the base 21 according to curved trajectories, whichform part of a circular arc in the embodiment shown. The radii 23 ofthese circular arcs are larger than the mutual distance thereof. Thecentrepoints of these curved trajectories are indicated at 24.

[0036] Each hand grip 3, 4 at its side facing the base 2 has anaccordingly curbed tooth rack 20 (not shown), which each engage theschematically shown pinions 21. These pinions 21 are rotatablyaccommodated in the base 2 according to an axis at the centrepoint 24 ofthe curbed trajectories. Each pinion 21 engages a central tooth wheel 22which is connected to a steering control (not shown).

[0037] As a result of the engagement of tooth racks, pinions 21 andtooth wheel 22, the movement of the hand grips 3, 4 is linked, that isan upward movement of one of the steering grips 3, 4 automatically leadsto a corresponding downward movement of the other of the steering grips3, 4.

[0038] Moreover, the tooth wheel 21 can be connected to an electricmotor for simulating steering resistance.

[0039] Furthermore, means may be provided which lock the steering grips3, 4 with respect to the base 2 in the case of a power failure. Also,means may be provided which release to the base 2 from its fixedposition, so as to make it rotatable around a backup steering axis insuch case of power failure. As a result, the steering device accordingto the invention can be used as a usual steering wheel, gripped at thesteering grips 3, 4, when a power failure occurs.

1. Steering device (1) for drive-by-wire functions in a vehicle,comprising a base (2) which can be fixed to the vehicle interior at thelocation of the driver, and two steering grips (3, 4) at opposite sidesof the base, which steering grips each can be gripped by a hand of thedriver, said steering grips (3, 4) being coupled and being moveable withrespect to the base (2) in mutually opposite directions.
 2. Steeringdevice according to claim 1, wherein the steering grips (3, 4) areslidable from their neutral position under the influence of a resistancedevice simulating steering resistance, e.g. a spring and/or an electricmotor and/or hydraulic means.
 3. Steering device according to claim 1 or2, wherein at least one sensor is provided for sensing a movement of thehandgrips, said sensor being in closed loop configuration with asteering control device.
 4. Steering device according to any of thepreceding claims, wherein the steering grips (3, 4) are coupled by meansof a tiltable lever (5), which at each end engages a respect steeringgrip (3, 4), and which midway between said ends is pivotably (7)connected to the base (2).
 5. Steering device according to claim 4,wherein the lever (5) engages each steering grip (3, 4) through aslidable/pivotable connection (6).
 6. Steering device according to claim2 and 4, wherein the resistance device is connected to the lever (5) forurging the steering grips (3, 4) towards their neutral position. 7.Steering device according to one of the preceding claims, wherein thebase (2) and/or the steering grips (3, 4) comprise(s) a display (10) andoperating buttons, e.g. for accelerating/decelerating, gear shifting,shifting indicators, lightning, route planning, telecommunication means,e.g. telephone.
 8. Steering device according to one of the precedingclaims, wherein the base (2) comprises an airbag (12).
 9. Steeringdevice according to one of the preceding claims, wherein each steeringgrip (3, 4) has a straight or arc-shaped outer circumference. 10.Steering device according to one of the preceding claims, wherein eachsteering grip (3, 4) has an arc-shaped rod (13), connected to a slide(14) which is slidable supported on the base (2).
 11. Steering deviceaccording to claim 10, wherein the rod (13) and slide (14) of eachsteering grip are connected through a spoke (15).
 12. Steering deviceaccording to one of the preceding claims, wherein the base (2) carries ahead-up screen or LCD screen for displaying vehicle control andperformance data, telecommunication means e.g. telephone, routeplanning.
 13. Steering device according to one of the preceding claims,wherein signalling means (16) are provided for signally a left-hand anda right-hand turn.
 14. Steering device according to any of the precedingclaims, wherein the steering grips are parallelly moveable.
 15. Steeringdevice according to any of the claims 1-13, wherein the steering gripsare moveably according to trajectories which are non-parallel. 16.Steering device according to claim 14 or 15, wherein each steering grip(3, 4) is slidable along the base by means of a linear bearing (9) e.g.a plain bearing.
 17. Steering device according to any one of claims1-13, wherein each steering grip (3, 4) is slidable according to acurbed trajectory.
 18. Steering device according to claim 17, whereinthe curbed trajectory of each steering grip (3, 4) is formed accordingto a circular arc.
 19. Steering device according to claim 18, whereinthe distance between the curbed trajectories is smaller than the sum ofthe radii of their circular arcs.
 20. Steering device according to claim19, wherein each steering grip (3, 4) has a tooth rack (20) which iscurbed according to the circular arcs, pinions (21) being rotatablyaccommodated in the base (2) which engage the curbed tooth racks (20).21. Steering device according to claim 20, wherein the pinions (21) eachengage a central tooth wheel (22), said central tooth wheel (22) beingconnectable to a steering control.
 22. Steering device according to anyof the preceding claims, wherein the basis (2) comprises a hand rest(23) which extends past the hand grips.
 23. Steering device according toclaim 11, wherein the rod (13) is connected to the slide (14) through apivot (24).
 24. In combination, a steering device (1) according to oneof the preceding claims, and a mechanically operated backup system (18)for controlling prime vehicle safety functions, such as steering andbraking in case of a power failure.
 25. Combination according to claim24, wherein locking means are provided for locking the steering grips(3, 4) with respect to the base (2) in the case of a power failure, saidfixed base (2) being linked to the backup system (18) and being releasedfrom a fixed position to a rotatable position in the case of said powerfailure.
 26. In combination, a steering device according to any ofclaims 1-25, and a steering column structure (18) comprising one or morefoot pedals (19) for e.g. acceleration and/or braking.
 27. Combinationaccording to claim 26, wherein the steering column structure (18)comprises electric lines and connector for connection to the vehicleelectronics car management.